What is the primary function of the prostate gland in the male reproductive system?

The primary function of the prostate gland in the male reproductive system is to produce a fluid that nourishes and transports sperm. This prostatic fluid is a key component of semen, making up approximately 30% of its volume. The fluid contains enzymes, citric acid, and other substances that help maintain sperm viability and motility during ejaculation, which is essential for fertility.

While the prostate does have other roles, such as contributing to the overall fluid composition of semen, its main function centers around supporting sperm. The production of this nourishing fluid is crucial because it provides a suitable environment for sperm to thrive as they travel through the female reproductive tract.

The other options relate to functions that are not primary to the prostate's role. Hormone production is more closely associated with the testes and adrenal glands, urine storage is primarily a function of the bladder, and while the prostate does have some role in contributing to barriers against infections, this is not its primary or most recognized function. The emphasis on the nutritional and transportation aspect of the prostate's fluid makes it clear why this option is the most appropriate answer regarding the gland's primary function.